User devices, such as smartphones, tablet PCs, cellular telephones, and portable digital assistants have become widespread and essential in consumers' everyday lives. Moreover, users personalize their user devices by downloading applications to their device or accessing applications via a web-browser. Each user device can have multiple users, and each user can use the device for a number of different reasons. For example, a user can use a user device for playing games, watching movies, listening to music, checking financial information, editing documents, and messaging friends.